Abstract. Deflorenne, Ph., Devillers-Terschuren, J. & Devillers, P.- Epipactis leptochila (Godfery) Godfery in the western Calestienne (Belgium) [Natural. belges 82 (Orchid. 14) (2001): 110-118]. Epipactis leptochila was first recorded in Belgium in 1981 and has never been known for more than a few stations localized on the Jurassic limestones of southern Belgian Lorraine and on the Palaeozoic limestones of the central and western Calestienne. Most of the stations in Lorraine and on the central Calestienne have now been reidentified as E. neglecta. The plants of the western Calestienne are E. leptochila s. str., and the area constitutes the main stronghold of the species in Belgium. The known stations are, however, very small and one of them appears to be declining. Conservation measures for the exceptional forest ecosystems in which they occur, in particular, beech forests with yew, Taxus baccata, are urgent. E. neglecta appears to have coexisted with E. leptochila in the area but to have been lost following clear-felling of forest sections.

Key-words: Orchidaceae, E. leptochila, E. neglecta, Belgium, Walloon Region, Lompret, Virelles, nature reserves, forestry practices.